finished default parser

src/Application/UseCases/MergeCollections.php

@@ -0,0 +1,15 @@
+<?php
+namespace XaiCorp\AbcParser\Application\UseCases;
+
+use XaiCorp\AbcParser\Domain\Core\TuneCollection;
+
+class MergeCollections
+{
+
+    public function merge(TuneCollection $masterCollection, TuneCollection $additions)
+    {
+        $collection = clone $masterCollection;
+
+        return $collection->merge($additions);
+    }
+}